JP3964601B2 - Protection system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a protection system for protecting a power system.
[0002]
[Prior art]
In substations and power plants in central Tokyo, the power bus configuration is divided into a plurality of unit buses, and the unit buses are connected by communication buses in order to maintain power supply reliability. Usually, substations in the city center are often linked by three transmission lines, and such an electric station constitutes three sets of unit buses.
[0003]
Fig. 10 shows the system configuration of the unit substation. In FIG. 10, 1, 2 and 3 are transformers for supplying power to each unit, 11, 21 and 31 are buses for each unit, 10 is a connecting bus, 12, 22 and 32 are load transmission lines for each unit, 101 , 102, 10T, 201, 202, 20T, 301, 302, and 30T are circuit breakers, respectively.
[0004]
Protection unit substation, in addition to the protection of each unit of the individual transformers 1-3 and each transmission line 12 to 32, as a protection of the equipment around each substation busbar unit bus 11 to 31 (usually protection and protection communication bus 10 of a single bus structure), breaker accident accident in order to prevent the spread to other units when continued connecting contact busbar and each unit when continues for a predetermined time or more Bus separation protection for opening 10T to 30T (bus communication breaker) is performed.
[0005]
FIG. 11 shows a bus protection device, a communication bus protection device, and a bus separation protection device of this unit substation. The symbols in FIG. 11 are the same as those described in FIG. 10 except for current transformers (CT) such as CT101, CT10T, and CT102. B10 in FIG. 11 shows a connecting bus protection device, and this current input generally employs a current differential protection method as a bus connecting CT (CT10T, CT20T, CT30T) of each unit.
[0006]
B11, B21, and B31 are bus protection devices for # 1, # 2, and # 3 units, respectively, and the current input is CT of the line connected to the unit bus. It has been adopted. Reference numerals BD1, BD2, and BD3 denote bus bar separation protection devices, and the current input is a bus bar contact CT.
[0007]
As shown in FIG. 11 , the conventional protection device for facilities centered on electric power station buses generally includes unit bus protection at B11 to B31 , communication bus protection at B10 , and BT1 to BT3 for each protection function. It is independent and configured by the bus separation protection in. And each busbar separation protection short circuit detecting means BT 1 through BT 3, protection relay having a direction means capable discrimination accidents direction is applied to both ground fault detecting means, the busbar breaker with a predetermined time limit Is released.
[0008]
In the case of a unit bus accident, the break point is in the own unit. In the case of a communication bus accident, the bus bar breaker of each unit is opened. Since current differential protection is adopted for the connection bus protection of B10, it is necessary to draw the secondary side of the current transformer (CT) installed in the bus connection of each unit into the connection bus protection device. Also, since the break point is the bus connection breaker of each unit, it is necessary to pass a break signal from the contact bus protection device to each unit.
[0009]
[Problems to be solved by the invention]
The connection bus protection of the conventional unit substation described above requires the CT secondary circuit to be routed outside the unit itself, so that it is not possible to maintain independence as a unit, and a connection bus protection device is provided for each unit. However, it does not solve the problem of CT, and it becomes an extremely expensive apparatus economically.
[0010]
The present invention has been made to solve the above-mentioned problems, eliminates the routing of CT, realizes the independence of a unit-unit protection device, and is economically excellent and has a comprehensive protection function. The purpose is to provide.
[0011]
[Means for Solving the Problems]
Protection system according to the claim 1 of the present invention, the plurality of units busbar in the protection system for the contact generatrix of the substation which is connected via a contact generatrix between the units bus, each unit bus unit A current differential relay Df for detecting an accident of the unit bus; and a current and a voltage from a current transformer and a transformer corresponding to each unit bus. A communication bus direction accident detection means (DI) for detecting an accident in the communication bus direction for connecting each unit bus, and a unit bus direction accident detection means (DO) in each unit, In the event of an accident, each of the current differential relays Df is operated to open the circuit breaker connected to the bus, thereby protecting the unit bus. When a communication bus accident occurs, the operation output of the communication bus direction accident detection means (DI), the non-operation output of the unit bus direction accident detection means (DO), and the units that mutually transmit between the protective devices A communication bus protection means for identifying and opening the circuit breaker from the communication bus direction accident information.
[0012]
Next, the operation will be described. The unit bus protection means can detect and remove the bus fault of the own unit. In addition, it is possible to detect the contact bus accident by combining the unit bus direction accident detection means DO and the contact bus direction accident detection means DI of the fault direction identification means using the voltage of the unit bus and the current from the contact bus direction accident detection means. If you do this, you can eliminate the contact bus accident by opening the bus contact breaker of your unit.
[0013]
In the protection system according to [Claim 2] of the present invention, in the communication bus protection means according to [Claim 1], the communication bus direction accident detection means (DI) and the unit bus direction accident detection means (DO) have. On the condition that the short-circuit accident detection means once operated, the operation range was expanded to a range including the origin, and the operation was continued.
[0014]
Next, to explain the action, said means DI means DO requires detected operation stability can be maintained even during short circuit for processing in units contact bus accident and the accident continue using the voltage loss at the time of short circuit If means DI or means DO due to the need to operate continuously even when is operated so that to continue the operation even if a non-voltage by Rukoto spread its operating range. As a result, it is possible to determine the contact bus accident and open the communication bus breaker of the unit when the accident continues, and at the same time, it is possible to handle the accident in units.
[0015]
In the protection system according to [Claim 3 ] of the present invention, in [Claim 1], the connection bus protection means detects an accident in the unit bus direction using a bus voltage and a bus connection current for each unit bus. Unit bus direction accident detection means (DO) and communication bus direction accident detection means (DI), the communication bus direction accident detection means (DI) of its own unit or other unit is operated, On the condition that any of the unit bus direction accident detection means (DO) is inoperative, it is determined that a communication bus fault has occurred and the bus bar breaker is opened .
[0016]
Next, the operation will be described. A combination of information on the DO and DI of the accident direction identification function using the voltage of the unit bus and the bus communication current is transmitted and received between the units, thereby determining the communication bus accident, A communication bus accident can be eliminated by opening the busbar circuit breaker of its own unit. Thereby, it is not necessary to directly draw the secondary circuit of the bus connection CT of the other unit into the own unit, and processing can be performed in unit units.
[0017]
The protection system according to [Claim 4 ] of the present invention is the protection system according to [Claim 1], wherein in the communication bus protection means, the communication bus direction accident detection means (DI) of its own unit operates and unit bus direction accident detection means ( When the DO) is inoperative, or the unit bus direction accident detection means (DO) of its own unit is inoperative and the accident detection means (FD) operates, and an accident in the direction of the connecting bus from other units (BTF) results. When receiving the information, the own unit transmits its signal to the other unit as an accident (BTF) in the communication bus direction, and when all the BTF signals received from the other unit are satisfied, The bus bar breaker was opened .
[0018]
Next, the operation of the connected bus direction will be explained. When the connected bus direction accident detection DI of the own unit is activated and the DO of the other unit is inoperative or the DI of the other unit is activated, the unit bus direction is detected. It can be determined that the means DO is inoperative. For this reason, when the DI of the own unit operates and the DO does not operate, or the accident detecting means (FD) of the own unit operates, the unit bus direction detecting means DO does not operate, and an accident in the direction of the connecting bus from other units When a signal (BTF) is received, it is determined that there is a communication bus accident. At the same time, it sends a signal of the connecting bus accident direction to other units. Similarly, the other unit determines that there is a communication bus accident on the condition that the BTF signal is received and that the own unit also has the BTF signal, and the bus communication circuit breaker is shut off. In this way, processing in units can be performed without routing the secondary circuit of the CT for bus communication of other units.
[0019]
In the protection system according to [Claim 5 ] of the present invention, in [Claim 4 ], the communication bus bar protection means transmits a condition that the bus bar circuit breaker or disconnector of its own unit is open to another unit. , The bus contact breaker is used as an accident (BTF) information in the direction of bus contact from the open unit .
[0020]
Next, the operation will be explained. When the busbar breaker or disconnector is open, the information on the busbar communication direction accident (BTF) from that unit cannot be obtained. Will always treat it as a bus contact direction accident. By doing so, the communication bus accident can be detected in units and handled.
[0021]
The protection system according to [Claim 6 ] of the present invention is the protection system according to [Claim 4 ], wherein the connection bus protection means uses unit bus direction accident detection means (DO) using a bus voltage and a bus connection current for each unit. ) Accident detection sensitivity is set in conjunction with the accident detection sensitivity of the communication bus direction accident detection means (DI) .
[0022]
Next, the operation will be described. By setting one of the accident detection sensitivity of the unit bus direction detection means DO or the accident detection sensitivity of the accident detection means DI in the connecting bus direction, the other accident detection sensitivity is automatically set. It is a thing. The unit DO that detects the outside as a communication bus accident in the event of a connection bus external accident needs to be more sensitive than the means DI of other units that detect the internal direction of the connection bus. If set, other means are automatically set, so there is no confusing setting and reliability is improved.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
(First Embodiment) (corresponding to [Claim 1])
FIG. 1 is an overall configuration diagram showing an embodiment of a protection system according to a first embodiment. In FIG. 1, the same functional parts as those in FIG. In this embodiment, protective devices RY1, RY2, and RY3 are provided for each unit bus, and currents from the current transformers CT101, CT102, CT10T, CT201, CT202, CT20T, CT301, CT302, and CT30T are input for each unit bus. In addition, the voltages from the transformers PT1, PT2 and PT3 are input. R11, R21, and R31 are signal lines for transferring information between the units.
[0026]
FIG. 2 is a schematic diagram of the internal configuration of the protection relay shown in FIG. Here, an example of RY1 of # 1 unit is shown. Each unit is provided with the same protective device as # 1. The protection device shown in FIG. 2 is a digital relay that takes the voltage and current of the system as inputs, digitally processes them, and uses the data to create a protection function. In the figure, the details are not directly related to the present invention, and therefore, other than the protection function is omitted.
[0027]
In FIG. 2, R0 indicates a protection relay means made by using the voltage and current of the # 1 unit, Df indicates a current differential relay for detecting an accident of the unit bus, and means DI indicates an accident in the direction of the connecting bus. The direction DO is a direction means for detecting an accident in the unit bus direction.
[0028]
These are performed using the bus voltage as a reference amount and the bus connection current for direction determination, and can be easily realized by, for example, a conventional short-circuit direction relay or ground fault direction relay. In addition to these relay means, there are accident detection means and the like, but they are omitted because they are complicated and do not relate to the description of the present invention.
[0029]
R1 represents the function of the three protection systems of the present invention, which are created by the operation of each relay means of R0. R2 is a unit bus protecting means, R3 is a bus separating means, and R4 is a connecting bus protecting means. Also, R11 is the contact bus direction accident information viewed from the # 1 unit, R21 is the contact bus direction accident information viewed from the # 2 unit, and R31 is the contact bus direction accident information viewed from the # 3 unit.
[0030]
Next, the operation will be described. When an accident occurs in the unit bus, the current differential relay means Df of the unit is operated to open the circuit breaker connected to the bus. When an accident occurs in the communication bus, the communication bus direction accident detection means DI of each unit is activated, and the unit bus direction accident detection means DO of each unit is determined to be inoperative, and it is determined as a communication bus accident. Open the circuit breaker connected to the bus.
[0031]
In the case of a load transmission line accident, the bus direction accident detection means DO of the unit concerned and the communication bus direction accident detection means DI of another unit operate, but since the means DO operates, it is not determined as a communication bus accident. When the power line breaker does not operate at the time of a power line accident, as described above, when the means DO continues to operate for a predetermined time or more, the bus line breaker of the unit is opened.
[0032]
According to the present embodiment, the unit bus accident can be determined by the unit alone, and even in the case of a communication bus accident, the relay operation information is turned on / off, and the accident spread by preventing the accident from occurring due to continued accidents. Detection processing is possible, and the system is simplified.
[0033]
Second Embodiment (corresponding to [Claim 2])
FIG. 3 is a block diagram showing the second embodiment, and is shown as a circuit for controlling the operating range of the fault detection means DI in the connecting bus direction and the unit bus direction accident detection means DO. FIG. 4 shows an example in which the operating range of the direction means in the R-X coordinate is widened by being offset backward.
[0034]
Next, the operation will be described. If an accident occurs in the bus, the bus voltage may be completely lost in a short-circuit accident, and the relay means that uses voltage as the polarity of the direction means loses its polarity, making it impossible to determine the direction. . If the direction cannot be determined, the direction of the accident cannot be identified, and there is a risk of deviating from the proper cutoff range.
[0035]
For this reason, it is necessary to ensure that the operation of the DI of the connecting bus direction accident detecting means and the short-circuit detecting means of the unit bus direction accident detecting means DO is surely continued even if the voltage is lost. Thus the short circuit detecting means of said means DI and means DO operate once, if the operating range including the origin in the R-X coordinate, the voltage at bus accident zero (origin) and continue operation can be achieved even when.
[0036]
According to the present embodiment, reliable operation can be continued and the external accident detection relay (DO) continues to operate even in the event of an accident outside the communication bus.
[0040]
( Third embodiment) (corresponding to [Claim 3 ])
FIG. 5 is a block diagram showing the third embodiment, which is a specific configuration example of the communication bus protecting means R4 in FIG. In this case, since it relates to each unit, the example of # 1 unit is shown for convenience. In FIG. 5 , DI1, DI2, and DI3 are accident detection means in the direction of the connecting bus of # 1, # 2, and # 3 units, and DO1, DO2, and DO3 are # 1, # 2, # 3, and # 3 units. It is an accident detection means in the direction of each unit bus. Any means DI operates each unit, any means DO of each unit also determines that the communication bus accident with the units on condition that inoperative, opening the busbar breaker.
[0041]
Next, the operation will be described. In the case of a contact bus accident, any means DI of each unit operates, and means DO does not operate in all units. In this case, it is determined that there is a contact bus accident, and each unit has a bus contact breaker. Open. On the other hand, since the unit DO of the unit operates in the case of a unit bus accident, it is not determined that there is a communication bus accident.
[0042]
According to the present embodiment, communication bus accident detection and accident handling can be performed on a unit basis by exchange of each unit, means DI, and means DO.
[0043]
( Fourth embodiment) (corresponding to [Claim 4 ])
FIG. 6 is a block diagram showing the fourth embodiment, which is a specific configuration example of the communication bus protecting means R4 in FIG. In this case, since it relates to each unit, the example of # 1 unit is shown for convenience. In FIG. 6 , DI1 is the # 1 unit communication bus direction accident detection means, and DO1 is the # 1 unit bus direction accident detection means. The FD is an accident detection means of # 1 unit and is constituted by undervoltage detection or ground fault overvoltage detection.
[0044]
BTF1, BTF2, and BTF3 are signals obtained as a result of determining the connecting bus accident direction in each unit. That is, in the figure, when the means DI1 operates, the means DO1 does not operate, or the means DO1 does not operate, the accident detection means (FD) operates, and the BTF1 signal is received when the BTF2 or BTF3 signal is received. Created. The determination as a contact bus accident is made when this BTF signal is established for all units.
[0045]
Next, the operation will be described. When all units are connected by communication buses and all units have power, if an accident occurs on the communication buses, means DI1 is activated, means DO1 is inoperative, and a BTF1 signal is sent to the other units. At the same time, BTF2 and BTF3 signals are transmitted from the other units to the # 1 unit in the same manner. For this reason, all units BTF1, BTF2, and BTF3 are established in the # 1 unit, and it is determined that there is a communication bus fault, and the bus bar breaker is opened.
[0046]
Similarly, the other units move in the same manner and open the bus bar breaker. When all units are connected by communication buses, the # 1 unit has no power supply in the back and the other units have power supply in the back, and if an accident occurs on the connection bus, the # 1 unit has an accident detection means (FD ) Operation and means DO1 non-operation are established, and BTF1 is transmitted upon reception of a BTF signal from another unit.
[0047]
In the other unit, the BTF is established by the means DI operation and the means DO non-operation, so the BTF signal is transmitted to # 1. From the above, in the # 1 unit, all of BTF1, BTF2, and BTF3 are established and it is determined that there is a communication bus accident, and the bus bar breaker is opened. Similarly, other units also establish a BTF signal and open the bus bar breaker.
[0048]
In the case of a unit bus accident, the bus protection device of the unit operates, and the associated circuit breaker is opened to eliminate the accident. In this case, when the unit DO of the unit operates, the BTF information of the unit is not established, and it is not determined that there is a communication bus accident. Needless to say, when the means DI or the means DO continues to operate, the bus bar breaker is opened at a predetermined time.
[0049]
According to the present embodiment, since the accident determination and the accident removal are performed independently for each unit, the complexity of the apparatus can be prevented and the reliability is improved.
[0050]
( Fifth embodiment) (corresponding to [Claim 5 ])
FIG. 7 is a block diagram showing the fifth embodiment. In the present embodiment, the BTF signal in FIG. 6 is not established when the busbar breaker or disconnector is open, so an open signal is transmitted. In FIG. 7 , 10T open indicates a bus connection release signal of # 1 unit, which is transmitted to # 2, # 3 units. 20T open indicates a bus contact release signal from the # 2 unit, and 30T open indicates a bus contact release signal from the # 3 unit. The 20T opening is composed of the BTF2 signal and OR, and the 30T opening is composed of the BTF3 signal and OR.
[0051]
Next, the operation will be described. In units where the busbar breaker or disconnector is open, the BTF signal will not be established in the event of a fault on the busbar. ) In place of the BTF signal.
[0052]
For example, if an accident occurs on the communication bus while the # 2 unit bus is open, the accident detection means cannot operate from the open unit and a BTF signal cannot be received, so it cannot be determined that the communication bus is protected. For this reason, when an accident occurs in the communication bus while the bus communication with the other unit is open, it can be determined that the communication bus has an accident by using the release signal from the opened unit instead of the BTF signal.
[0053]
According to the present embodiment, it is possible to provide a protection system capable of performing an accident detection and processing independently by a unit regardless of the operating state of the system.
[0054]
( Sixth embodiment) (corresponding to [Claim 6 ])
FIG. 8 is a block diagram showing the sixth embodiment. The sensitivity of the connecting bus direction accident detection means DI and the unit bus direction accident detection means DO provided to realize the connecting bus protection means R4 of FIG. It is a setting example figure. 8 is a circuit for setting the operation sensitivity of the relay means, where the operation sensitivity is set for each means. In the example as 8 (a) is a dynamic sensitivity of the means DO operation sensitivity settling them if the value k times has been unit DI, Fig. 8 (b) settling the operation sensitivity of the device DI In this example, the value is multiplied by 1 / k to obtain the operation sensitivity of the means DO.
[0055]
Next, the operation will be described. The communication bus protection is to determine whether there is an accident on the communication bus from the operation status of the means DI and DO of each unit. It is necessary to coordinate the operation sensitivity of the unit means DO, or the means DI of the other unit and the means DO of the own unit.
[0056]
For example, if an accident occurs in the power transmission line of the own unit, the means DI of the other unit operates and it is determined that there is a communication bus direction accident. You have to keep it. Thus, the means DO needs to have higher sensitivity than the means DI.
[0057]
Considering the case where there is one current connection bus inflow terminal and two outflow terminals due to an external accident on the connection bus, this difference in operation sensitivity is at least 1/2 or more higher than the means DI. There is a need to. On the other hand, means DI and DO may also be used as busbar separation protection means. In this case, there is generally no problem even if the operation sensitivity is changed, and there is no problem even if the same settling is performed.
[0058]
Therefore, when the means DI and the means DO are shared by the bus separation protection means and the connection bus protection means, it is necessary to consider the connection bus protection means, and the settling operator needs to pay extra effort. . In the present embodiment, when one of the operation sensitivities of the means DI and the means DO is set, the other is automatically set to a predetermined sensitivity, so that the setting can be simplified and reliable.
[0059]
According to the present embodiment, when one of the means DI and the means DO is set, the sensitivity of the other means is automatically set, and the settling failure of the means DI and the means DO that require operation sensitivity coordination is prevented. Can do.
[0060]
【The invention's effect】
As described above, according to the present invention, it is possible to determine a unit bus fault and a communication bus fault by a single unit, and it is possible to constitute a simple and economical protection system by also having a bus bar separation protection means. it can.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.
FIG. 2 is a configuration diagram showing a first embodiment of the present invention.
FIG. 3 is a configuration diagram showing a second embodiment of the present invention.
FIG. 4 is a characteristic explanatory diagram of a second embodiment of the present invention.
FIG. 5 is a configuration diagram showing a third embodiment of the present invention.
FIG. 6 is a configuration diagram showing a fourth embodiment of the present invention.
FIG. 7 is a block diagram showing a fifth embodiment of the present invention.
FIG. 8 is a block diagram showing a sixth embodiment of the present invention.
FIG. 9 is a general system diagram having a communication bus.
FIG. 10 is a diagram illustrating a device configuration of a conventional protection device.
FIG. 11 is a diagram illustrating a protection function of a conventional device .
[Explanation of symbols]
1,2,3 transformer
101, 102, 10T, 201, 202, 20T, 301, 302, 30T circuit breaker
CT101, CT102, CT10T, CT201, CT201, CT20T, CT301, CT302, CT30T Current transformer PT1, PT2, PT3 Transformer RY1, RY2, RY3 Protection device 11, 21, 31 Bus of each unit 10 Connection bus 12, 22, 32 Load transmission line of each unit R11, R21, R31 Signal line

Claims (6)

Wherein a plurality of units busbar in the protection system for the contact generatrix of the substation which is connected via a contact generatrix between the units busbars, corresponding to each said respective units busbar said protection device to the unit bus units respectively provided The current and voltage from the current transformer and the transformer to be input are input, the current differential relay Df for detecting the fault of the unit bus and the fault in the direction of the connecting bus for connecting each unit bus to the protective device. A communication bus direction accident detection means (DI) for detecting and a unit bus direction accident detection means (DO) in each unit are provided, and each current differential relay Df operates when an accident occurs in the unit bus. Open the circuit breaker of each line connected to the bus and protect the unit bus, and in the event of an accident of the communication bus, The circuit breaker is detected from the operation output of the accident detection means (DI), the non-operation output of the unit bus direction accident detection means (DO), and the communication bus direction accident information from each unit that is transmitted between each protection device. A protection system characterized by comprising a connection bus bar protection means that is specified and opened . According to claim 1, wherein the protection system, in the contact busbar protection means, provided that the short-circuit failure detecting means for the contact generatrix direction fault detection means (DI) and the unit generatrix direction fault detection means (DO) has has operated once , the protection system, characterized in that to continue the operation to expand the operating range in the range including the origin. 2. The protection system according to claim 1, wherein the communication bus protection means communicates with a unit bus direction accident detection means (DO) for detecting an accident in the unit bus direction using a bus voltage and a bus connection current for each unit bus. A bus direction accident detection means (DI), and the communication bus direction accident detection means (DI) of the own unit or another unit is operated, and either of the unit bus direction accident detection means (DO) of the own unit or the other unit A protection system comprising: determining that a communication bus accident has occurred and opening the bus connection breaker on condition that the device is inoperative . In請Motomeko 1 wherein the protection system, in the contact busbar protection means, if contact generatrix direction fault detection unit of its own terminal unit (DI) operates and the unit generatrix direction fault detection means (DO) is not operating, or own unit If the unit bus direction accident detection means (DO) of the unit is inoperative and the accident detection means (FD) is operated and the information on the communication bus direction accident (BTF) from another unit is received, the own unit will contact the bus As a direction fault (BTF), the signal is transmitted to the other unit, and when all the BTF signals received from the other unit are established, the bus disconnection circuit breaker of the own unit is opened as a communication bus fault. Protection system. 5. The protection system according to claim 4, wherein the communication bus protection means transmits a condition that the bus connection circuit breaker or disconnector of its own unit is opened to another unit, and the unit where the bus connection circuit breaker is opened. Protection system characterized by being used as accident (BTF) information in the direction of bus contact from 5. The protection system according to claim 4, wherein the communication bus protection means uses a bus voltage and a bus connection current for each unit to set the fault detection sensitivity of the unit bus direction accident detection means (DO) to the communication bus direction accident. A protection system that is set in conjunction with the accident detection sensitivity of the detection means (DI) .

Images